Asus hides the SMBus PCI bridge within the ICH2 or ICH4 southbridge on
Asus P4B/P4PE mainboards. The attached patch adds a quirk to re-enable the
SMBus PCI bridge for P4B533 and P4PE mainboards.
Dominik
diff -ru linux-original/drivers/pci/quirks.c linux/drivers/pci/quirks.c
--- linux-original/drivers/pci/quirks.c 2003-03-19 22:13:57.000000000 +0100
+++ linux/drivers/pci/quirks.c 2003-03-19 22:14:52.000000000 +0100
@@ -647,6 +647,53 @@
}
/*
+ * On ASUS P4B boards, the SMBus PCI Device within the ICH2/4 southbridge
+ * is not activated. The myth is that Asus said that they do not want the
+ * users to be irritated by just another PCI Device in the Win98 device
+ * manager. (see the file prog/hotplug/README.p4b in the lm_sensors
+ * package 2.7.0 for details)
+ *
+ * The SMBus PCI Device can be activated by setting a bit in the ICH LPC
+ * bridge. Unfortunately, this device has no subvendor/subdevice ID. So it
+ * becomes necessary to do this tweak in two steps -- I've chosen the Host
+ * bridge as trigger.
+ */
+
+static int __initdata asus_hides_smbus = 0;
+
+static void __init asus_hides_smbus_hostbridge(struct pci_dev *dev)
+{
+ if (likely(dev->subsystem_vendor != PCI_VENDOR_ID_ASUSTEK))
+ return;
+
+ if ((dev->device == PCI_DEVICE_ID_INTEL_82845_HB) &&
+ (dev->subsystem_device == 0x8088)) /* P4B533 */
+ asus_hides_smbus = 1;
+ if ((dev->device == PCI_DEVICE_ID_INTEL_82845G_HB) &&
+ (dev->subsystem_device == 0x80b2)) /* P4PE */
+ asus_hides_smbus = 1;
+ return;
+}
+
+static void __init asus_hides_smbus_lpc(struct pci_dev *dev)
+{
+ u16 val;
+
+ if (likely(!asus_hides_smbus))
+ return;
+
+ pci_read_config_word(dev, 0xF2, &val);
+ if (val & 0x8) {
+ pci_write_config_word(dev, 0xF2, val & (~0x8));
+ pci_read_config_word(dev, 0xF2, &val);
+ if(val & 0x8)
+ printk(KERN_INFO "PCI: i801 SMBus device continues to play 'hide and seek'! 0x%x\n", val);
+ else
+ printk(KERN_INFO "PCI: Enabled i801 SMBus device\n");
+ }
+}
+
+/*
* The main table of quirks.
*/
@@ -724,6 +771,13 @@
{ PCI_FIXUP_HEADER, PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82375, quirk_eisa_bridge },
+ /*
+ * on Asus P4B boards, the i801SMBus device is disabled at startup.
+ */
+ { PCI_FIXUP_HEADER, PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82845_HB, asus_hides_smbus_hostbridge },
+ { PCI_FIXUP_HEADER, PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82845G_HB, asus_hides_smbus_hostbridge },
+ { PCI_FIXUP_HEADER, PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0, asus_hides_smbus_lpc },
+
{ 0 }
};
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
